Problems with Kcross.inhom
Again, your problem is not reproducible. We do not have the objects
"north", "west", "W" and "tipo" which are necessary to duplicate your
steps.
I tried to reproduce your problem with an artificial example:
W <- owin(c(0,3350),c(0,6150))
set.seed(42)
Z <- runifpoint(201,win=W)
m <- sample(rep(c("ficus","tienda"),c(131,70)),201)
marks(Z) <- factor(m)
ff <- with(split(Z),bw.diggle(ficus))
tt <- with(split(Z),bw.diggle(tienda))
lambdaf <- with(split(Z),density(ficus,ff,at="points"))
lambdat <- with(split(Z),density(tienda,tt,at="points"))
K <- Kcross.inhom(Z,"ficus","tienda",lambdaf,lambdat)
No problema.
It is possible that the error has something to do with the rather intricate
(1716 vertices) boundary of your observation window. However since I don't
have that window I can't tell.
cheers,
Rolf Turner
On 10/22/13 10:16, david.villalobos wrote:
Sure Julia, First: I have the following object called "Z"
Z <- ppp(north, west,window=W,marks=tipo) summary(Z)
Marked planar point pattern: 201 points
Average intensity 4.46e-05 points per square unit
Coordinates are integers
i.e. rounded to the nearest 1 unit
Multitype:
frequency proportion intensity
ficus 131 0.652 2.90e-05
tienda 70 0.348 1.55e-05
Window: polygonal boundary
single connected closed polygon with 1716 vertices
enclosing rectangle: [484546.8, 487897.4] x [1147521.3, 1153682.9] units
Window area = 4509680 square units
Second:
I calculated the bandwidth sigma for the kernel estimator of point process
intensity with a Cross Validated Bandwidth Selection for Kernel Density
(bw.diggle)
attach(split(Z)) f<-bw.diggle(ficus) t<-bw.diggle(tienda)
Third: I calculated with the Kernel Smoothed Intensity of Point Pattern (density.ppp) the values of the the estimated intensity of the sub-process of points of type i and j:
lambdaf<-density.ppp(ficus,f,at="points") lambdat<-density.ppp(tienda,t,at="points")
and Finally: I ran the script for Kcross.inhom for the method (1): estimate intensities by nonparametric smoothing, but I had the error.
K <- Kcross.inhom(Z, "ficus", "tienda", lambdaf, lambdat)
Error in Kwtsum(dclose, bI, weight, b, 1/lambdaI, breaks) : Weights in K-function were infinite or NA I tryed the method (2): leave-one-out, but I had the same problems Any help is appreciated. A lot of thanks. -- View this message in context: http://r-sig-geo.2731867.n2.nabble.com/Problems-with-Kcross-inhom-tp7584914p7584920.html Sent from the R-sig-geo mailing list archive at Nabble.com.
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